1. Technical Field
The present disclosure is generally directed towards the field of photoacoustic (PA) imaging. More particularly, exemplary embodiments of the present disclosure are directed towards apparatus, systems and methods for the production of highly compact illumination schemes whereby PA waves are induced. Exemplary embodiments of the present disclosure are also directed towards apparatus, systems and methods for the production of a compact and portable, integrated transducer-illumination array (TIA).
2. Background Art
Photoacoustic (PA) imaging is a non-invasive medical imaging technique that may be used for detecting vascular and dermatological diseases, e.g., skin and breast cancers. The PA effect (as first reported in 1880 by A. G. Bell) arises wherein a target sample becomes heated due to absorption of light, producing an increase in pressure and/or volume of the material and its surroundings. By modulating the intensity of the light, the resulting periodic variation in pressure and/or volume can be detected as ultrasonic (US) waves. The US waves can ultimately be converted to near-real time two or three-dimensional images of the target sample using various mathematical equations. Thus, PA imaging provides relatively inexpensive and effective near real-time high-contrast imaging with relatively little danger to the target sample.
Prior apparatus, systems, and methods for PA imaging generally employ a single low-energy near-infrared laser to illuminate the target sample using a single US transducer. See, for example, “Optoacoustic Tomography,” Oraevsky and Karabutov, Biomedical Photonics Handbook, P 34-1, 2003, CRC Press LLC, “Ultrasound-mediated biophotonic imaging: A review of acousto-optical tomography and photo-acoustic tomography,” Disease Makers 19, P. 123-138 (2003-2004); U.S. Pat. No. 4,255,971 to Rosencwaig, “Thermoacoustic Microscopy;” U.S. Pat. No. 5,070,733 to Nagata and Koda, “Photoacoustic Imaging Method;” U.S. Pat. No. 5,840,023 to Oraevsky et al., “Optoacoustic Imaging for Medical Diagnosis;” U.S. Pat. No. 6,212,421 to Vo-Dinh et al., “Method and Apparatus of Spectro-Acoustically Enhanced Ultrasonic Detection for Diagnostics;” U.S. Pat. No. 5,977,538 to Unger and Wu, “Optoacoustic Imaging System;” U.S. Pat. No. 6,979,292 to Kanayama et al., “Method and Apparatus for Forming an Image that shows information about a subject;” U.S. Pat. No. 6,833,540 to MacKenzie et al., “System for measuring a biological parameter by means of photoacoustic interaction;” and U.S. Pat. No. 6,846,288 to Nagar et al., “Photoacoustic Assay and Imaging System.”
Of note, prior art teachings do not provide adequate means for selectively illuminating a target sample under a US transducer array. For example, Niederhauser et. al. disclose a glass prism illumination scheme for a US transducer array that is not sufficiently compact and/or portable and therefore not very practical for in-field PA imaging applications. [See, Niederhauser et. al., IEEE Transactions on Medical Imaging, Vol. 24, No. 4, Page 436, April 2005.] Additionally, existing illumination schemes do not enable control of illuminated patterns or geometries and/or to match the disparate illumination patterns and geometries with various transducers/transducer arrays on the market.
Generally, apparatus, systems and methods are needed that produce/provide compact illumination schemes. Furthermore, apparatus, systems and methods are needed that produce/provide compact illumination schemes of controllable patterns and/or geometries. Indeed, production of dynamically controllable illumination schemes would be particularly advantageous. Additionally, there is a need for apparatus, systems and methods that compactly integrate such illumination schemes with one or more ultrasonic transducers/ultrasonic transducer arrays.
These and other needs are satisfied by the disclosed apparatus, systems and methods described herein.